Label-free 1D microfluidic dipstick counting of microbial colonies and bacteriophage plaques
Sultan İlayda Dönmez, Sarah Needs, Helen M. I. Osborn, Nuno M. Reis, Alexander D. Edwards
Abstract
. This may be explained by the microenvironment offered for 1D colony growth within microcapillaries, linked to a mass balance between nutrient (glucose) diffusion and bacterial growth kinetics. Counting individual colonies in liquid medium was not possible for motile strains that spread rapidly along the capillary, however inclusion of soft agar inhibited spreading, making this new simple dip-and-test counting method applicable to both motile and non-motile bacteria. Label-free dipstick colony and plaque counting has potential for many analytical microbial tasks, and the innovation of 1D colony counting has relevance to other microfluidic microbiology.